Figure 4.

Activin A does not promote phosphorylation of ERK or Akt in cultured DRG neurons. A, Representative Western blots of p-ERK and p-Akt production in rat DRG neurons after 10 min of exposure to control vehicle, 1.0, 2.5, 5.0, and 10 ng/ml activin A (A) as well as 100 ng/ml NGF (N), respectively. B, Normalized density of bands [(phospho-protein/corresponding total protein)/internal control actin] for the indicated treatments. Each bar represents mean ± SEM of six (Akt) or seven (ERK) density measurements. *p < 0.01 and **p < 0.0001 compared with respective controls.